Improved blast-furnace



W. RASCHETTE.

Bleistfurnace.

Patented J une:21, 1864.

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VVOLDEMAR RASCHETTE, OF ST. PETERSBURG, RUSSIA, ASSIGNOR TO ALEXANDERTRIPPEL, OF NEW YORK CITY.

IMPROVED BLAST-FURNACE.

Specification forming part of Letters Patent No. 43,274, dated June 21,1864.

To all whom it may concern.-

Be it known that I, WOLDEMAR RASOHETTE, of St. Petersburg, Empire ofRussia, have in vented a new and Improved Blast-Furnace; and I do herebydeclare that the following is a full, clear, and exact description ofthe same, reference being had to the accompanying drawings, forming apart of'this specification, in which- Figure 1 represents a transversevertical section of my invention, taken in the plane indicated by theline as m, Fig. 2. Fig. 2 is a longitudinal vertical section of thesame, the plane of section being indicated by the line 1 3 Fig. 1. .Fig.3 is a horizontal section of the same, the line 2 2, Fig.1, indicatingthe plane of section. Fig. 4 is a similar section of the same, taken inthe plane indicated by the line w m, Fig. 1. Figs. 5 and 6 areperspective views of the slotted air-chambers detached.

Similar letters of reference in the several views indicate correspondingparts.

This invention consists, first, in a blast-furnace the hearth of which,when bisected by a horizontal plane, presents a narrow long rectangle,the two short sides of which are to be used as working sides, and itstwo long sides for two or more rows of tuyeres, and whose long and shortsides increase gradually from the hearth up to a point near the throatin such a manner that a perfectly steady and gradual descent of thecharges from the throat to the hearth is effected, and the ore, fuel,and fluxes (as charged in horizontal layers) preserve the same relativeposition toward each other while descending from the throat to thehearth of the furnace; and, furthermore, the reduction of the ore can beeffected in less time and with less fuel than it can in a furnace of theordinary construction.

It consists, further, in the employment or use, in combination with along rectangular hearth, of a double row of tuyeres, each tuyere beingplaced so as to be between two of the opposite side, in such a mannerthat a smelt ing and oxidizing zone of uniform temperature and littlevertical depth is obtained throughout the entire length of the furnace,and the process of reducing the ore is effected with less fuel and inless time than in furnaces having the tuyeres arranged in the ordinarymanner.

It consists, further, in the arrangement of one or more fire-places andfire-fines under the bottom and through the walls of the furnace in sucha manner that a uniform and quick heating of the external walls of thefurnace during the erection of the same, and particularly previous tolighting the charge in its interior, can be effected, and thereby thesuccessful working of the furnace is rendered practicable and itsdurability considerably increased.

It consists, finally, in the employment or use of slotted air-chambersin place of or in combination with the tuyeres in such a manner that thecost of the mechanism used for introducing the blast into the furnace isconsiderably reduced without diminishing or impairing the effect.

To enable those skilled in the art to make and use my invention, I willproceed to describe it.

A represents a furnace built according to my invention. Its foundationis formed of brick-work or walls B, and through these walls lead thechannels I) d e, terminating on one side of the furnace in thefire-place c and 'on the opposite side in the opening 0. The channels bd e distribute the hot or cold air under the bottom of the hearth G ofthe furnace, and they serve either to heat the walls of the furnaceprevious to starting the fire in the same or to cool off said wallsafter the charge has been removed.

In order to heat or cool the side walls of the furnace, the horizontalchannels 6 communicate with vertical channels f, and separate horizontalchannels 9, Fig. 2, serve to carry off the moisture and to cool off thewalls. The channels I; d e are covered bya cast-iron plate, h, whichsupports the bottom 2' of the hearth. This hearth is made in the form ofalong narrow rectangle, see Fig. 3,) and its bottom is either made ofone solid stone or it is constructed of some suitable fire-proof composttion laid on the plate h to the desired thickness, firmly ra1nmedfTheside walls, 70, of the hearth are built up of fire-brick, and the boshesZ are lined with some fire-proof composition. The long sides of thehearth are perforated with a series ofsemicircular holes, m, to serve asthe tuyeres, and these tuyeres terminate in the chambers a, extendingthrough out the whole length of the furnace, or nearly so. The tuyeresare so divided over the long sides of the furnace that those on one sideare opposite the spaces between those on the opposite; or, instead ofthese tuyeres, slotted air-chambers 111* may be used, through which theblast is introduced in an unbroken plane on either of the long sides ofthe furnace. The sides 0 are lined with the best fire-brick, and theyrest on the walls 12, being strengthened and supported by cast-ironplates and beams, the latter being inserted in the narrow or workingside of the furnace. Each of the narrow working sides of the furnace isprovided with a discharge-opening, t, as clearly shown in Fig. 2 of thedrawings. The outer walls of the furnace rest upon cast-iron columns a,supported by platesr, and the whole brick-work is strengthened andsupported by suitable iron bands and hoops in the usual manner. The mainair-channels O are supported by suitable hooks or brackets secured to.the long sides of the furnace, and from these air-channels extend theblast-pipes h to the tuyeres gn; or one or more pipes, 71*, conduct theblast to the slotted air-chambers m By referring to Figs. 1 and 2 of thedrawings it will be observed that my furnace gradually enlarges from thehearth up to its mouth or throat. The vertical section across its twolong sides forms a trapezoid, having the largest of its parallel sidesat or across thethroat, and the smallest at the hearth, and the verticalsection across the two short sides forms either a rectangle or atrapezoid, with the length and height of the furnace as its principaldimensions.

The principal points of difference between the form of my furnace andthose previously used is found in its great length in one and itsnarrowness in the other direction; further, in the gradual andprogressive increase of its cubical capacity as it approaches the throatfurther, in the much reduced height compared with the height of furnacesnow used for iron ores. The advantages resulting from these improvedforms are, first,the charges descend perfectly steady and gradually fromthe throat to the hearth, quite different from the irregular descent ofthe charges in the furnaces constructcd in the ordinary manner;secondly, the ore, fuel, and flux (as charged in horizontal layers)maintain their relative position toward each other during their descentfrom the throat to the hearth; thirdly, the caloric contained in theheated gases produced by the combustion of the fuel in the smelting zoneand ascending in the furnace over a gradually-enlarging surface is morecompletely absorbed by the charge in my furnace than it is in a furnaceof the ordinary construction, and thereby a great saving of fuel iseffected fourthly, in consequence of the reduced height of my furnacethe charges have to stay a much shorter time in the same and the yieldof metal is larger, while the consumption of the fuel is smaller than ina furnace of the ordinary construction; finally, the

pressure of the blast can be greatly reduced, the construction of myfurnace is cheaper, and the charges can be easier elevated to the levelof the furnace-throat than in an ordinary furnace.

By my new arrangement of tuyeres or slotted air-chambers thesmelting-zone situated in the plane passing th rough said tuyeres orair-chambers is rendered more uniform, extensive, and intensive than byany other blast arrangement heretofore used, and in consequence thereofthe time for the passage of the charges is reduced andthe fuel perfectlyutilized.

By the application of a system of fines under and in the furnace-walls,I am enabled to dry a newly-constructed furnace from the exterior to theinterior, instead of the reverse, as heretofore practiced; and,furthermore, by these flues the radiation of heat from the sides of thefurnace during its operation is pre vented. These flues, in which theatmospheric air is either in motion or at rest, as the case may be, formgood non-conductors for heat,

and by their action the temperature of the upper zones of the furnace isdecreased. a

A furnace constructed according to my invention costs less to build thana furnace of the ordinary construction. It can be worked with lessexpenditure of fuel, and the yield of metal is increased.

It must be remarked that with slight alterations in the constructionthis furnace is applicable for the reduction of copper, zinc, or otherores besides iron ore.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is v 1.. A blast-furnace, A, the hearth ofwhich, when bisected by a horizontal plane, presents a narrow longrectangle, the short sides of which are to be used as working sides, andthe two long sides for two or more rows of tuyeres, and whose long andshort sides increase gradually from the hearth up to a point near thethroat, substantially in the manner and for the purposes herein shownand described.

2. The employment or use, in combination with a long rectangular hearth,of a double row of tuyeres, each tuyere being placed so as o be betweentwo of the oppositeside, in thet manner and for the purposesubstantially as specified.

3. The arrangement of one or more fireplaces and a series of fire-finesunder the bot: tom and through the walls of the furnace A,

constructed and operating in the manner and for the purposesubstantially as set forth.

4. The slotted air chambers, substituting and in combination with thetuyeres, and applied to the furnace A, substantially as and for thepurpose described.

WVOLDEMAR RASGHETTE.

Witnesses:

OBERET BEINEKE, F. Russow.

